1. Field of the Invention
The present invention relates to a semiconductor manufacturing technique, and more particularly, to an apparatus for fixing heat-adherent taping members to a lead frame during the manufacture of semiconductor devices. This apparatus is referred hereinafter to as a "taping apparatus". This invention also relates to a method of adhering a heat-adherent taping member to a lead frame.
2. Description of the Related Art
In a taping apparatus conventionally known in the art of semiconductor manufacturing technology, the elongated flexible tape has a structure consisting of two or more layers, i.e., an insulation base film made of a suitable resin, for example, a polyimide film strip, and a heat-adherent layer formed on upper and/or lower surface of the film base. The heat-adherent layer usually is not adhesive at a room temperature but becomes adhesive when heated. The elongated tape is punched and cut to form individual taping members each having a desired configuration, which are then pushed against a heated lead frame, whereby the taping members are continuously adhered to the lead frame.
In this taping apparatus, the heat-adherent tape is intermittently fed through a die, which continuously punches and cuts the tape into individual taping members each having a predetermined shape, the taping member is then lowered and pushed against a lead frame resting on and heated by a heater block located under the die, whereby the taping member is heat-adhered to the lead frame. The means used for continuously and intermittently feeding the tape through the die comprises a pair of feed and pinch rollers located downstream of the die, the feed roller being driven by a suitable pulse motor. The tape is passed through the gap between the pair of rollers of this feeding means and then intermittently fed through the die.
Recently, however, a greater sophistication is required from a taping member for lead frames, and thus the tolerances of the taping member must be more strictly controlled with regard to the shape or dimension thereof; e.g., to within .+-.0.05 mm or .+-.0.07 mm. Also, a much thinner tape is now used to make the taping members.
Therefore, if such a thin, flexible tape is fed through the die by the above-mentioned conventional feeding means, the tape would be subjected to a tension force in the die, and thus tape might be deformed therein. Where the tape has pilot apertures, since the tape is under a tension, the apertures might be deformed by a misinsertion of pilot pins of the die, when the pilot pins are inserted to the pilot apertures. Under such circumstances, it becomes difficult to accurately position the tape at a predetermined position in the die, and thus accurate by formed taping members can not be obtained.